Object Oriented ABAP

Actual result – 24.
Expected Result – 25.
Tolerance – 0.9999.
Difference = Expected Result - Actual result.
= 1 > tolerance.
Therefore displays an error.
Example Program:
Let us consider an example for ABAP unit test using the method ASSERT_EQUALS to check
the equality of two data objects. In this program, we have two methods divide and factorial
in a local class MATH. We want to test the factorial method. So we have created one class
and one method MYTEST for testing. In the test method implementation we have called the
factorial method and so the data object RESULT is populated. Now we are going to compare
the actual data object (RESULT) with the expected result. For that we are calling the
ASSERT_EQUALS from the global class passing the expected result.
*----------------------------------------------------------------------*
* CLASS math DEFINITION
*----------------------------------------------------------------------*
*
*----------------------------------------------------------------------*
CLASS math DEFINITION.
PUBLIC SECTION.
METHODS divide
IMPORTING opr1 TYPE i
opr2 TYPE i
EXPORTING result TYPE f
RAISING cx_sy_arithmetic_error.
METHODS factorial
IMPORTING n TYPE i
RETURNING value(fact) TYPE i.
ENDCLASS. "math DEFINITION
*----------------------------------------------------------------------*
* CLASS math IMPLEMENTATION
*----------------------------------------------------------------------*
*
*----------------------------------------------------------------------*
CLASS math IMPLEMENTATION.
METHOD divide.
result = opr2 / opr1.
ENDMETHOD. "divide
METHOD factorial.
fact = 1.
IF n = 0.
RETURN.
ELSE.
DO n TIMES.
fact = fact * sy-index.
ENDDO.